CBSE Questions for Class 11 Medical Chemistry Environmental Chemistry Quiz 12 - MCQExams.com

There is cut off signal when NASA rocket reaches in the region of _________.
  • D-layer
  • Stratosphere
  • Ozone layer
  • Mesosphere
Which of the following are main responsible for ozone depletion?
  • Chlorofluorocarbons
  • Hydrocarbons
  • Carbon monoxide
  • Carbon dioxide
The reaction that is NOT involved in the ozone layer depletion mechanism in the stratosphere is:  
Biochemical Oxygen Demand (BOD) is a measure of organic material present in water. BOD of Clear water is
  • 17 ppm or more
  • More than 20 ppm
  • Less than 5 ppm
  • 5-10 ppm
Which of the following is not an example of green chemistry?
  • Reacting methylamine and phosgene to produce methyl isocyanate
  • replacement of CFCs by $${ CO }_{ 2 }$$ as blowing agent in the manufacture of polystyrene foam sheet
  • catalytic dehydrogenation of the diethanol amine without using cyanide and formaldehyde
  • replacement of organotins by 'sea-nine' as antifouling compound in sea marines
Which of the folowing oxides of nitrogen is not a common air pollutant ?
  • $$ NO_2$$
  • $$ N_2O $$
  • $$ NO $$
  • $$ N_2O_5 $$
Stopping the usage of insecticides means _________.
  • Control on using insecticides
  • Ban on insecticides
  • Following Eco-friendly agricultural methods
  • Bio-chemical reaction
Choose the incorrect option:
  • The amount of B.O.D in water is a measure of the amount of organic matter present in the water sample.
  • Higher B.O.D values indicates that water is pure.
  • The required fluoride amount in drinking water is 1 ppm above 2 ppm it gives serious harmful effects.
  • The maximum nitrate limit is 50 ppm and excess causes methemolobinemia.
The pollutant that causes hole in the ozone layer is
  • $$SF_{6}$$
  • nitrousoxide
  • $$CFC_{s}$$
  • $$PFC_{s}$$
_____________ is the first country to have phased out the CFCs and HCFCs which are responsible for the depletion of the ozone layer
  • Denmark
  • Germany
  • France
  • Spain
Which of the following is depleted by CFCs?
  • Atmosphere
  • Ozone Layer
  • Biosphere
  • Hydrosphere
Snow blindness is caused due to 
  • Global warming
  • Ozone depletion
  • Greenhouse effect
  • Bio magnification
Which of the following has highest concentration of PAN?
  • Smoke
  • Ozone
  • Photochemical smog
  • Reducing smog
Melanornia (skin cancer) is associated with
  • ozone accumulation
  • ozone depletion
  • acid rain
  • allergens
In land filling, insecticides are sprayed on top, to prevent
  • Bad odour
  • Breeding of mosqitoes
  • Preventing ground water pollution
  • All of above
What gases are involved in ozone depletion?
  • Nitrogen
  • Chlorine and Bromine
  • Chlorofluorocarbons (CFCs) and Ozone Depleting Substances (ODS)
  • Both B and C
What does a single chlorine free radical destroy?
  • Ultraviolet radiations
  • Atmosphere
  • Biosphere
  • Ozone layer
Which chemical is a 'ozone' depleting solvent?
  • PAN
  • CFCs
  • Carbon tetrachloride
  • Nitrogen
'HCFCs' can be used in refrigerants instead of
  • $$CO_{2}$$
  • Chlorine
  • CFCs
  • $$O_{2}$$
HCs are thermodynamically not stable towards
  • Acidification
  • Decomposition
  • Reduction
  • Oxidation
Free radicals of bromine are more destructive than _______ in case of ozone depletion.
  • Carbon
  • Chlorine
  • Phosphorous
  • Nitrogen
How long does a refuse take in getting stabilized?
  • 3 months
  • 2-12 months
  • 3-7 months
  • 9 months
Spray are formed by atomization of parent liquids; such as:
  • Pesticides and herbicides
  • liquid particulate
  • Gaseous matters
  • Solid matters
What causes effects of ozone layer?
  • Alpha Radiations
  • Ultraviolet Radiations
  • Gamma radiations
  • Beta Radiations
The ozone hole over Antarctica was discovered in the
  • 1955
  • 1965
  • 1970
  • 1985
What is involved in ozone depletion?
  • Chlorofluorocarbons (CFCs)
  • Carbon tetrachloride (CCl4)
  • Carbon tetrafluoride (CF4)
  • All of above
Tropospheric ozone harmful effects on humans, included:
  • Chest pain
  • Throat irritation
  • Vomiting
  • Both A and B
Chlorine free radical reacts with 'ozone' to form _______.
  • CFCs
  • Chlorine oxide
  • $$N_{2}$$
  • Bromine oxide
Which among the following alkane has largely replaced the ozone layer-depleting halomethanes in household refrigerators and freezers?
  • Methane
  • Propane
  • Butane
  • Ethane
The hydrochlorofluorocarbons (HCFCs) are the compounds that have the following molecules: hydrogen, carbon, chlorine, fluorine. Which among the above plays the most important role in ozone depletion?
  • Hydrogen
  • Carbon
  • Chlorine
  • Flourine
In SOCs, most common organic pollutants are:
  • DDT
  • Weed killers
  • Pesticides, Herbicides
  • Sprays
At which of the following places First Global Conference on depletion of Ozone layer was held?
  • Geneva
  • Vienna
  • London
  • Frankfurt
'Nitric acid' reacts with ozone, resulting in the production of __________.
  • $$O_3$$
  • CO
  • $$CO_2$$
  • $$NO_2$$
Tetraethyl lead (TEL) in petrol was used as antiknocking agent, which creates lead pollution. In order to avoid lead pollution, the substitute of TEL is used in unleaded-petrol. The substitute is denoted as: 
  • $$AK-33-X$$
  • $$BK-33-X$$
  • $$CK-33-X$$
  • $$DK-33-X$$
Which of the following type of pollution causes the out break of jaundice ?
  • Air pollution
  • Water pollution
  • Soil pollution
  • thermal pollution
Which of the following has highest knocking property?
  • Aromatic hydrocarbons
  • Olefins
  • Branched chain paraffms
  • Straight chain paraffins
Which nitrate on decomposition will give metal ?
  • $$Hg_{2}(NO_3)_2 $$
  • $$NaNO_3 $$
  • $$KNO_3 $$
  • $$AgNO_3 $$
$$BOD_5$$ is:
  • Waste decomposed in $$5$$ days
  • Oxygen used in $$5$$ days
  • Microorganisms killed in $$5$$ days
  • Dissolved oxygen left after $$5$$ days
0:0:1


Answered Not Answered Not Visited Correct : 0 Incorrect : 0

Practice Class 11 Medical Chemistry Quiz Questions and Answers